{"schema_version":"secwatch.filing_event.v1","accession":"0001193125-21-331813","form_type":"8-K","ticker":"BIIB","cik":"0000875045","company_name":"BIOGEN INC.","filed_at":"2021-11-17T23:59:59+00:00","discovered_at":"2026-05-14T18:04:15.937946+00:00","generated_at":"2026-06-28T07:35:26.018895+00:00","sec_items":["5.02","9.01"],"event_type":"leadership","sentiment":"neutral","materiality_score":0.55,"calibrated_materiality_score":0.55,"confidence":"high","headline":"Biogen R&D head Alfred Sandrock to retire Dec 31, 2021; interim named","bullets":["Alfred W. Sandrock, Head of R&D, will retire effective Dec 31, 2021, after 23 years at Biogen.","Priya Singhal, Head of Global Safety & Regulatory Sciences, will serve as interim R&D head.","Sandrock led development of key drugs: Tysabri, Tecfidera, Spinraza, Plegridy, and Aduhelm.","Biogen has launched a search for a permanent successor."],"urls":{"canonical":"https://secwatch.observer/filing/0001193125-21-331813","json":"https://secwatch.observer/filing/0001193125-21-331813.json","markdown":"https://secwatch.observer/filing/0001193125-21-331813.md","text":"https://secwatch.observer/filing/0001193125-21-331813.txt","edgar_index":"https://www.sec.gov/Archives/edgar/data/875045/000119312521331813/0001193125-21-331813-index.htm","edgar_primary_document":"https://www.sec.gov/Archives/edgar/data/875045/000119312521331813/d257656d8k.htm"},"model":{"generated_by":"deepseek-v4-flash:cloud@v2","generated_at":"2026-06-28T07:35:26.018895+00:00"},"review":{"review_status":"machine_generated","human_reviewed":false,"corrected":false,"correction_note":null,"correction_timestamp":null,"superseded_by":null,"related_filings":[]},"source_grounded_claims":[{"claim_id":"764bbec4a6","claim":"Alfred W. Sandrock, Jr., M.D., Ph.D. departed as Head of Research & Development at BIOGEN INC..","evidence_excerpt":"On November 15, 2021, Biogen Inc. (the “Company”) issued a press release announcing that Alfred W. Sandrock, Jr., M.D., Ph.D., Head of Research & Development, will retire from the Company, effective December 31, 2021.","evidence_source":"SEC 8-K Item 5.02","evidence_url":"https://www.sec.gov/Archives/edgar/data/875045/000119312521331813/0001193125-21-331813-index.htm","confidence":0.95,"family_label":"Executive change","details":[{"label":"Action","value":"retire"},{"label":"Role","value":"Head of Research & Development"}],"fact_type":"executive_change"}],"license":"Source filings: public domain (SEC EDGAR). Summaries (headline + bullets): CC-BY-4.0; attribute https://secwatch.observer"}